1. Technical Field
The present invention relates to an imaging lens assembly. More to particularly, the present invention relates to a compact imaging lens assembly applicable to electronic products.
2. Description of Related Art
In recent years, with the popularity of mobile products having camera functionalities, the demand of miniaturized optical lens systems has been increasing. The sensor of a conventional optical lens system is typically a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor. As the advanced semiconductor manufacturing technologies have allowed the pixel size of sensors to be reduced and compact optical lens systems have gradually evolved toward the field of higher megapixels, there is an increasing demand for compact optical lens systems featuring better image quality.
A conventional optical lens system employed in a portable electronic product mainly adopts a four-element lens structure or a five-element lens structure such as the ones disclosed in the U.S. Pat. No. 7,869,142 and the U.S. Pat. No. 8,000,031. Due to the popularity of mobile products with high-end specifications, such as smart phones and PDAs (Personal Digital Assistants), the requirements for high resolution and image quality of present compact optical lens systems increase significantly. However, the conventional optical lens system cannot satisfy these requirements of the compact optical lens systems.
Other conventional compact optical lens systems with six-element lens structure such as the one disclosed in the U.S. Publication No. 2012/0206822 A1 enhance image quality and resolution. However, the shape of the surfaces of the fifth lens element cannot effectively control the angle at which the incident light projects onto an image sensor from every field, so that the vignetting is generated on the peripheral region of the image and the image quality is decreased. Furthermore, the size of the optical lens system cannot be effectively reduced, and cannot be applied to the portable assembly.